摘 要: 针对视觉同步定位与地图构建领域中基于深度相机传感器的算法前端跟踪耗时长,精度差的问题,提出了一种 RGB-D SLAM 算法的前端视觉里程计实现方案。依据传统的视觉里程计 实现方案,采用 ORB 特征提取算法对图像进行特征提取并计算描述子,与局部地图中地图点进行 特征匹配,最后采用 PnP 算法计算相机位姿。为提高算法跟踪的精准度,提出在计算相机位姿后, 利用三角测量进行局部地图中地图点深度的更新。实验采用 TUM 数据库中 fr1 系列数据集进行测 试,结果表明,该算法在保证实时性的同时,使跟踪过程中的均方根误差平均减小了 9. 21% 。且 fr1 系列两种数据集通过视觉里程计最后生成点云地图的图像信息熵比传统 RGB-D SLAM 系统平均 提高了 11. 21% 。
Abstract
In view of the long time-consuming and poor precision of RGB-D SLAM algorithm in the field ofvisual SLAM,an implementation scheme of RGB-D SLAM visual odometry is proposed. Based on the traditional visual odometer implementation scheme,the ORB feature extraction algorithm is used to extract the features of the image and calculate the descriptor to match the features of the map points in the local map. Finally,the PnP algorithm is used to calculate the camera pose. In order to ensure the accuracy of the tracking,it is proposed to use the triangulation algorithm to update the depth of the map points in the local map after calculating the camera pose. The experiment uses fr1 series data set in tum database to test. The experimental results show that the scheme can reduce the root-mean-square error in the tracking process by 9. 21% on average while ensuring real-time performance. The image quality of the point cloud map generated is also improved by 11. 21% .